<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>

    <style>
        ul li {
            width: 20px;
            height: 20px;
            background-color: gray;
        }
    </style>
</head>
<body>
    <ul class="my">
        <li>1</li>
        <li>2</li>
        <li>3</li>
        <li>4</li>
        <li>5</li>

    </ul>
    

    <script>
        // var lis=document.getElementsByClassName('my');
        // console.log(lis);
        // lis.addEventListener('click',(e)=>{
        //     console.log(e.target.innerHTML);
        // })
        
        var liss=document.querySelector('ul');
        console.log(liss);
        function fn(){
            console.log('傻逼');
        }
        
        liss.addEventListener('click',fn)

        liss.removeEventListener('click',fn)
    </script>
</body>
</html>